Tetrahydrophthalic alkyd resins



Patented Oct. 13, 1953 2,655,486 TETRAHYDROPHTHALIC ALKYD RESIN S Alexander 0. Keyl, Bensenville, and Robert H. Geils, Downers Grove, Ill., assignors to Fredk A. Stresen-Reutcr, Inc., a corporation of Illinois No Drawing. Application September 27, 1950,

Serial No. 187,129

9 Claims. (Cl. 260-22) This invention relates to tetrahydrophthalic alkyds and more particularly to improved oil modified alkyd resins derived from tetrahydrophthalic acid and to methods of producing the same.

In our copending application Serial No. 187,130 filed of even date herewith, we have disclosed the production of a tetrahydrophthalic acid halt ester intermediate of a mono fatty ester of a polyhydroxy aliphatic alcohol having the following formula:

or the isomeric structure wherein some or the as half ester is upon a different hydroxyl:

wherein R is the alkyl, alkenyl, or hydroxy alkenyl typical long chain residue of saturated or groups distributed not more than one hydroxyl group for each carbon atom; R is hydrogen or a monocarbocyclic 5 or 6 carbon atom ring radin-octyl, decyl, decenyl, dodecyl, oleyl and hexadecyl; and X is hydrogen or halogen such as chlorine or bromine.

This intermediate is a viscous liquid stable at As indicated, the oil modified alkyd resin produced from such intermediate has an average aliphatic chain length of 10 to 22 carbon atoms a harder resin capable of produced hard films and having substantial resistance to water, acids or alkalies.

In general, oil length of a resin, for purposes herein, may be quantitatively classified as:

Fatty acid per cent Short oil alkyd 45-50 Medium oil alkyd 50-60 Long 011 alkyd -75 wherein the percentages are weight percent of fatty acid with respect to total resin.

tion of the intermediate with mono or polybasic organic acids to introduce, as a monobasic acid, a resin type of acid such as pimaric, naphthenic, abietic or other mono acids of a resinous or resin forming type including such resin acids which may have been hydrogenated, of which the rosin acids are preferred, but other typical dibasic organic acids of the character of phthalic acid, maleic acid, succinic acid, citric acid, adipic acid, sebasic acid or their anhydrides normally use in alkyd resin formation may be used for further modification of the intermediate to produce short oil alkyds.

Thus, it is the primary object of the present invention to resinify a tetrahydrophthalic acid ha ester intermediate of a fatty acid ester of a polyhydric aliphatic alcohol as defined above to form resins of the alkyd type of controlled oil length. Other objects will be inherent in the description hereof.

For modifying the intermediate according to the present invention, it is reacted in proportions which may vary rather widely such as from equal proportions of intermediate and modifying component to from 3 mols of intermediate to 0.1 mol of modifier, but preferably in the range of 3 mols of intermediate to from 1 to /4, of a mol of the modifying component, the modifying component being of the character listed above such as a polyhydric alcohol, or a mono or dibasic organic aci of which the monobasic acid may be a resin acid or fatty acid. The reaction, in general, ofthe intermediate with one of these modifying agents is modifier preferably by dissolving both reagents in a solvent capable of azeotropic distillation, such as an aromatic or aliphatic naphtha, preferably tillate of aromatic or aliphatic character, boil ing in the range of 150 to 400 F. The solution is then azeotropically distilled at the temperature of azeotropic distillation over a period of 5 to 20 hours, continuously separating the water of condensation from the distillate and continuously recycling the solvent to the still as the condensa tion proceeds. v i

It is possible to effect reaction of the intermetaneously therefrom a mod'fied' resin by directly heating the mixture in the same temperature range for an analogous period of time. However, this latter method is not preferred inasmuch as some decompos'tion may take place.. Where the latter method is used it is preferable-to effect the condensation by heating the mixture under a blanket of inert gas such as carbon dioxide or nitrogen.

The resinous condensate usually has an acid value of less than 50 and it may have an acid value of substantially zero where the condensation is carried to the end point. It will be understood that it is not essential to carry the condensation to the end point unless acid reacting pigments such as zinc oxide are to be mixed with the resin in forming a coating composition, in which event it is essential that the resin be substantially neutral.

1. Direct resinificatlon of the half ester without modification Intermediate medium oil water half ester heat modified alkyd The intermediate is dissolved in: the solvent and mixing the intermediate with the diate with the modifying agent to produce sinful-'- toluene, xylene or a coal tar or petroleum oil di'sazeotropically distilled by heating to the distillation point of the solvent and moisture of condensation. The condensate is collected outside of the still. The water distilled with the solvent is separated and the solvent is continuously returned to the still. The end point of resinification is determined when no more water comes over and the acid value has been reduced to less than 50. Alternatively, the azeotropic distillation may be effected by direct passage of steam into the resin solution in the volatile solvent. Alternatively direct resinification of the intermediatemay be effected by heating the same without a solvent under an inert gas blanket of carbon dioxide. The resin formed in solution may be used directly or the solvent may finally be separated.

2. Reaction of the intermediate with a fatty acid to produce a long oil modified alkyd resin The resin intermediate and fatty acid are dissolved in the solvent in proportion of 3 mols of intermediate to from 1 to /4 of 9. mol of a fatty acid, which may be the same or different than the fatty acid already contained esterified in the intermediate. Where the resin is to be used as a coating composition, the fatty acid is preferably an unsaturated fatty acid derived from a drying oil such as linseed oil, tung oilor soy bean oil, but the fatty acid may be derived from any oil or fat such as fish oil, lard, stearin, palm oil, peanut oil, coconut oil or castor oil. Both the intermediate and the fatty acid are dissolved in the hydrocarbon solvent to approximately a 50 to 80% solution and azeotropically distilled to remove water of condensation and form the oil modified alkyd resin of the long oil type having a high oil content such as from 60 to of the resin.

3. Reaction of the intermediate with a. polyhydric aliphatic alcohol to produce a short oil modifled alkyd resin The half ester intermediate is mixed with a polyhydric alcohol of the character of ethylene diethylene glycol,

glycol, trimethylene glycol, propylene gIycoL'butylene glycol, glycerol, polyglycerol, mannitol, sorbitol, pentaerythritol or dipentaerythritol in proportion preferably of 3 mols of intermediate to from 1 to mols of polyhydric alcohol, and dissolved in a solvent capable of azeotropic distillation such as the hydrocarbon solvents mentioned above. The solution in 50 to strength is azeotropicall-y distilled over a period of 2 to 20 hours to produce a short oil type alkyd resin predominating in hydroxy groups. Resins of this type produce hard films. 4. Reaction of intermediate with monobas'ic resin acids'to produce a resin-modified alkyd resin The intermediate is mixed with a m'onoba'sic resin acid having at least one free carboxyl group such as rosin acids, naphthenic acids, orh'ydr'ogenated products thereof, in proportion preferably of 3' mols oi intermediate to from 1 to mol of th resin acid, and reacted by distilling the solvent from the dissolved mixture in 50 to 80% solution over a period of 2' to 20 hours. The resin produced is a hard alkyd resin of short oil character. A similar procedure is used to produce a resin by modification of the in termediate with a dibasic acid.

EXAMPLE I An intermediate as described in my co-pendingapplication is preparedby first reacting the monoglycerid of soy bean oil fatty acid with maleic of reagents anhydride in equimolar proportions and heating the same under a blanket of inert gas at a temperature of 180 F. until an acid value of 122.70 was obtained. This product was then dissolved xylene to form a 70% solution, mixed with liquid. 1,3 butadiene equimolar proportions and heated in an autoclave with stirring for 36 hours at a temperature of 115 F. and a pressure of pounds per square inch. The product had an at room temperature.

The tetrahydrophthalic acid half ester was disin xylene to form a 48% a viscosity of A--l of 94.0 (Gardner) and an acid value of 12. To the solution of 48% nonvolatile resinified solids in xylene, a drier com prising a mixture of a 0.5% lead naphthenate 0.05% cobalt naphthenate based upon the nonvolatile solids was added. The solution was then distributed as a film on glass and air dried.

film was found to have a slip While as indicated the intermediate of this example is originally formed from soy bean oil 1,3 dienes other than butadiene or." this example such as 4-phenyl butadiene 1-3, 4- toluyi butadiene 1-3, .i-cycloherzyl butadiene 1-3, 4( 2 methyl cyclo pentyl) butadiene l--3, l-chloro pentadiene 1-3, 4-isopropyl butadiene 1-3, hexadiene 1-3, iii isobutyl butadiene 1-3, heptadiene 1-3, oetadiene 1-3, l-bromo pentadiene l-3, 4 dodecyl butadiene l 3. Any of such intermediates may be substituted in this and other examples hereof as the intermediate.

EXAMPLE II The intermediate as obtained in Exampie I is dissolved as a 70% solution in mineral spirits consisting of an aliphatic petroleum naphtha of tetrahydrophthalic acid to 1 mol of rosin containing about 90% of abietic acid and 10% pi maric acid, and azeotropically distilled at a tem- F. with continuous separation of the water of condensation and Viscosity Q plus (Gardner-Holdt) Color 12 plus (Gardner 1933) Acid value 50.4 (determined on non-volatile matter) Non-volatile matter 74% solution of the resin obtained in this example was mixed with a standard drier consisting of 0.05% of cobalt metal and 0.5% lead metal based on the non-volatile matter content of the solution added as naphthenates. A 0.003 film glass and was found to dry dust free after 5 hours and 15 minin an air drying oven and baked at of 200 F. and set tack free in 3 hours.

EXAMPLE III ner-Holdt) value 9.1, no

applied to glass. The film dried dust free after six hours and 40 minutes and set to touch after 8 hours and 20 minutes. After 24 hours the film showed a very slight tack to touch. A similar ture of 200 F. was found to be tack free after six hours of baking time.

By way of comparison the intermediate alone condensed in a series of heating periods under the EXAMPLE IV Three mols of the intermediate of Example I A of a mol of linseed oil fatty mixture as a value of 24 and was found to dry tack free on a 0.003" film of glass in 24 hours. In this example any fatty acid having from 10 to 22 carbon atoms may be substituted V to exact control carboxylic acid group or one or more free hy' intermediate,

an intermediate product,

for, the linseed oil to produce long oil resins hereof EXAMPLE v The intermediate of Example I was mixed in proportion of 3 mols of intermediate with one mol of maleic anhydride and azeotropically distilled as a 75% solution in xylene over a period of 4 hours and minutes. The product had an acid value of 4:5. It dried to a hard resinous coating in an air drying oven at a temperature of 200 F., and was tack free in 6 hours. In this example various dibasic acids and anhydrides thereof listed above may be substituted for the maleic anhydride.

As thus described valuable oil modified resins are prepared by further modification and resinification of an intermediate tetrahydrophthalic acid half ester of a mono fatty ester of a polyhydric alcohol by heating such an intermediate with an additional drying oil fatty acid, a polyhydric aliphatic alcohol, a monobasic resin acid or a polybasic organic acid preferably in an azeotropic distillation in a solvent to continuously remove water of condensation, for simultaneous esterification of these acids or alcohols with either a free hydroxyl radical or carboxyl radical contained in the intermediate, and simultaneous condensation of an oil modified alkyd resin of read'ly controlled oil length,.drying properties and widely variable properties of the'resin per so.

As thus described the resins herein are subject of esteriiication of either a free droxyl groups contained in a stable with mono or polybasic organic carboxylic acids or with a polyhydric alcohol to produce an alkyd resin by a simultaneous esterification and condensation wherein all of the components are reacted to form a unitary resin compound as distinguished from unreacted mixtures. Thus exact control of the oil length for an oil modified alkyd resin is possible as well as the character ,of the resin itself, i. e. as to hardness or flexibility of film, the solubility thereof in various solvents, and the rate of drying or resistance to drying, as desired.

Various modifications of these alkyd type resins are possible as are known in the art of formation of alkyd resins. If desired the intermediate hereof may be modified with various mixtures of monobasic and dibasic organic acids, including monobasic acids of either drying or non-drying fatty acids as well as rosin acids. Such acid mixtures may further be used with mixtures of additional polyhydric alcohol. The resinification may be effected in the presence of modifiers such as plasticizers and drying agents. The resins afterformation may also be mixed with pigments, drying oils and other resins, etc.. as are known inthe resin and coating arts to form improved coating compositions of the oil modified resin type as well as resins for other uses.

It is accordingly intended that the examples given herein be regarded as illustrative and not limiting except as defined in the claims.

We claim: I v 1. The method of forming an prising simultaneously esterifying and condensing meric tetrahydrophthalic acid 'half ester of a monoester of a 10 to 22 carbon atom fatty acid with a polyhydric aliphatic alcohol having at leastthree hydroxyl groups, With an esterifying agent selected from the group consisting of a, It) to 22 carbon atom fatty acid, a natural resin acid and hydrogenation products thereof, a polycare boxylic organic acid and anhydrides thereof and polyhydric aliphatic alcohols.

2. The method of forming an alkyd resin comprising simultaneously esterifying and condensing an intermediate product having the formula:

wherein R is selected from the group consisting of the alkyl and alkenyl radicals of a fatty acid having from 19 to 22 carbon atoms; R is selected from the group consisting of hydrogen, an alliyl radical having 1-3 carbon atoms and a lower alkanol radical having 1-3 carbon atoms substituted with 1'3 hydroxyl groups distributed not more than 1 hydroxyl group for each carbon atom; R is selected from the group consisting of hydrogen, .a monocarbocyclic radical having 5-6 52-16 carbon atoms; 2

' consisting of hydrogen and halogen, with an es terifying agent selected from the group consisting of a 10 to 22 carbon atom fatty acid, a natural resin acid and hydrogenation products thereof, a polycarboxylic organic acid and anhydrides thereof and polyhydric aliphatic 3. The method of forming an alkyd resin comprising simultaneously esterifying and condensing an intermediate product, comprising a monomeric tetrahydrophthalic acid half ester of a monoester of a 10 to 22 carbon atom fatty acid with a polyhydric alphatic alcohol having at least three hydroxyl groups, with an esterifying agent consisting of a fatty acid having 10 to 22 carbon atoms.

4. The method of forming an alkyd resin comprising simultaneously esterifying and condensing an intermediate product, comprising a monomeric tetrahydrophthalic acid half ester of a monoester of a 10 to 22 carbon atom fatty acid with a polyhydric aliphatic alcohol having at least three hydroxyl groups, with an esterifying agent consisting of a drying oil fatty acid.

5. The method of forming an alkyd resin comprising simultaneously esterifyingeand condensing an intermediate product, comprising a mono: meric tetrahydrophthalic acid half ester of a monoester of a 10 to 22 carbon atom fatty acid with a polyhydric aliphatic alcohol having at least three hydroxyl groups, with an esterifying agent consisting of a natural resin acid.

6. The method of forming an alkyd resin comprising simultaneously esterifying and condensing'an intermediate product, comprising a monomeric tetrahydrophthalic acid half ester of a monoester of a 10 to 22 carbon atom fatty acid with a polyhydric aliphatic alcohol having at least three hydroxyl groups, with an esterifying agent consisting of an anhydride of a polycarboxylic organic acid.

1. The method of forming an alkyd resin come prising simultaneously esterifying and condensing an intermediate product, comprising a monotilling said solution to remove water of condenmeric tetrahydrophthalic sation.

9. The method of forming an alkyd resin comprising simultaneously esterifying and condensconsisting of a polycarboxylic organic acid.

ALEXANDER C. KEYL. ROBERT H. GEILS carbon atom fatty acid, a natural resin acid and 15 Refemnces Cited m the me of this Patent hydrogenation products thereof, a polycarboxylic UNITED STATES PATENTS organic acid and anhydrides thereof and poly- T hydric aliphatic alcohols, by first dissolving the 2 32 g gi in rmediate half ester compound and esterifymg 2057765 Brubaker Oct 1936 agent 1n proportion of 3 mols of intermediate to 20 2251297 soday g, 1941 from 1 to of a mol of esterifymg agent in a 2385776 1?; Oct 1945 volatile organic solvent capable of azeotropic dis- 2404836 Gerhart et tillation with water, and then azeotropically dis- 

1. THE METHOD OF FORMING AN ALKYD RESIN COMPRISING SIMULTANEOUSLY ESTERIFYING AND CONDENSING AN INTERMEDIATE PRODUCT, COMPRISING A MONOMERIC TETRAHYDROPHTHALIC ACID HALF ESTER OF A MONOESTER OF A 10 TO 22 CARBON ATOM FATTY ACID WITH A POLYHYDRIC ALIPHATIC ALCOHOL HAVING AT LEAST THREE HYDROXYL GROUPS, WITH AN ESTERIFYING AGENT SELECTED FROM THE GROUP CONSISTING OF A 10 TO 22 CARBON ATOM FATTY ACID, A NATURAL RESIN ACID AND HYDROGENATION PRODUCTS THEREOF, A POLYCARBOXYLIC ORGANIC ACID AND ANHYDRIDES THEREOF AND POLYHYDRIC ALIPHATIC ALCOHOLS. 